I had opera 16+ installed for quite some time but still used 12 because of the missing features in 16+.
But yesterday I decided to take a leap and switch to 20. Opera 12 is indeed boggled up and if it only takes one year for some of the new pages to stop working I can't imagine how hard the guys at Opera had to maintain it.
Also I wanted to stop myself switching to Chrome just because of those sites that weren't working.
Adapting to changing environments is a good exercise in getting ... better in adapting